I was demanded to give alimony agreed even before filing a petition for mutual consent. How and when is it good to handover and record the transaction if handedover before so that they can't demand more in future and can't be able to trouble us.

Please make these payments at the time of recording the statement in mutual consent divorce petition before the court. Please pay half at the time of first motion and half at the time of recording of statement of second motion. this is the safest option you can have.